The present invention relates to the field of devices for dispensing a predetermined quantity of liquid from a pressurized source in response to each actuation of the device. It finds particular, but not exclusive, utility for dispensing viscous liquids such as ketchup. The device lends itself to advantageous use in fast food operations where careful quantity control of the dispensed liquid is important to the quality of the product and the economics of the operation.
A wide variety of devices for dispensing measured quanities of liquid have been devised heretofore. Such prior devices have numerous shortcomings, including complexity, expense, difficulty in dismantling for cleaning purposes, imprecise measuring of liquid dispensed, or difficulty in handling liquid from a pressurized source.